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A MANUAL OF BACTERIOLOGY 



portion terminates in a small orifice, and is also 

 provided with a minute lateral opening.' The tube 

 and arm a contain mercury. Reichert's regulator is 

 fixed into the roof of the incubator, so that its 



FIG. 16. KARL ABEL'S INCUBATOR. 

 (With thermo-electric regulator.) 



lower portion projects either into the water chamber 

 or into the interior of the incubator. 'When the 

 incubator reaches the required temperature, the 



